Two steps forward, one step back

As molecular imaging continues to evolve, there will be some growing pains to go along with the successes. Recent top stories in molecular imaging have illustrated both the ups and the downs.

On the negative side, amyloid imaging has suffered some setbacks after early optimism. It was a hot topic at the annual meeting of the Radiological Society of North America (RSNA) last month in Chicago. In one neuroimaging symposium session, Alexander E. Drzezga, MD, from Harvard University Medical School in Boston, discussed the limitations of amyloid imaging for monitoring Alzheimer’s disease progression, saying amyloid is not ideal because as many as 25 percent of cognitively healthy patients reveal some amyloid accumulation. Amyloid levels also peak and plateau in Alzheimer’s patients, further limiting the utility of longitudinal data.

Anti-amyloid drug studies have also not provided much encouragement. “The view of anti-amyloid drugs is disappointing so far,” said Drzezga, noting that anti-amyloid drug therapy results in incomplete or very mild symptom relief even when substantial amyloid removal is achieved.

Earlier this year, the Centers for Medicare and Medicaid Services (CMS) issued a coverage decision on amyloid imaging that placed it under coverage with evidence development (CED) only. This means the imaging must be in the context of a clinical trial.

Oncologic FDG was also slowed by another CMS decision this year. Coverage for oncologic FDG studies was limited to three scans, and the leg work required to receive approval has depressed the market, said Peter Burke, vice president of sales and marketing for IBA Molecular. FDG study volumes have been down 5-10 percent since the decision, according to Burke.

There’s still plenty to be positive about in the field of molecular imaging, however. The latest in PET/CT and PET/MR technology was on display at RSNA, and a report from BCC Research said the molecular imaging technology market will expand in the coming years at a compound annual growth rate of 6.2 percent, reaching $3 billion by 2018.

Researchers from Chang Gung Memorial Hospital in Taoyuan, Taiwan, also scored a victory in the study of Parkinson’s disease. They demonstrated that F-18 DTBZ PET could be a useful tool in differentiating Parkinson’s from normal aging during the early stage of the disease, according to a study published online Nov. 28 in the Journal of Nuclear Medicine.

It will be interesting to see what successes molecular imaging researchers will achieve in the coming year.

Evan Godt
Editor – Health Imaging